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J Am Soc Mass Spectrom. 1990 Nov;1(6):448-54. doi: 10.1016/1044-0305(90)85028-K.
Plasma diagnostic studies have been carried out on the discharge source of a commercial glow discharge quadrupole mass spectrometer. Plasma parameters were determined using an electrostatic probe with the objective of determining the dependence (if any) of these parameters on the voltage placed on an auxiliary electrode immersed in the plasma. The biased electrode utilized in this study was the sampling orifice element itself. Our results indicate that, for positive orifice voltages with respect to the grounded anode, variations in the plasma potential and ion energy can be correlated directly to the bias placed on the sampling orifice. The dependence of the electron temperature on this parameter is observed to be more complex in nature, and electron number densities show little significant variation with respect to sampling orifice bias. In addition, increased orifice voltages result in an increase in the ion signal intensity measured with the mass spectrometer. Based on the results obtained here, we feel that this increase is due primarily to an increase in ion transmission to the quadrupole arising from the increased ion energy.(J Am Soc Mass Spectrom 1990, 1, 448-454).
已对商业辉光放电四极质谱仪的放电源进行了等离子体诊断研究。使用静电探针确定了等离子体参数，目的是确定这些参数是否取决于浸入等离子体中的辅助电极上的电压。本研究中使用的偏置电极是取样孔元件本身。我们的结果表明，对于相对于接地阳极的正孔电压，等离子体势和离子能量的变化可以直接与取样孔的偏置相关联。观察到电子温度对该参数的依赖性在本质上更为复杂，而电子数密度相对于取样孔偏置几乎没有明显变化。此外，孔电压的增加会导致质谱仪测量的离子信号强度增加。基于这里得到的结果，我们认为这种增加主要是由于离子能量增加导致离子向四极传输增加所致。（J Am Soc Mass Spectrom 1990, 1, 448-454）。
